This document introduces several popular open source Android libraries, including Android Annotations for clean code generation, Android Query for asynchronous tasks, Active Android for ORM, Mapsforge for maps, ACRA for crash reporting, Picasso for image loading, and achartengine for charts. It provides brief descriptions and links to documentation for each library. The author is identified as Murat Aydin, an Android developer and blogger who leads GDG Ankara events.